Reversible pitch engine fan operating mechanism



REVERSIBLE PITCH ENGINE FAN OPERATING MECHANISM Filed Feb. 11. 1955 P. F. 'STEINER May 5, 1959 3 Sheets-Sheet l INVENTOR.

May 5, 1959 2,885,013

REVERSIBLE PITCH ENGINE FAN OPERATING MECHANISM Filed Feb. 11. 1955 P. F. STEINEVR 3 Sheefts-Sheet 2 INVENTOR.

BY m 0. l

May 5, 1959 P. i STEINER 2,385,013

REVERSIBLE PITCH ENGINE FAN OPERATING MECHANISM Filed Feb. 11. 1955 s Sheets-Sheet s IN V EN TOR.

REVERSIBLE PITCH ENGINE FAN OPERATING NIECHANISM Phillip F. Steiner, Chicago, Ill., assignor to International Harvester Company, a corporation of New Jersey Application February 11, 1955, Serial No. 487,585

6 Claims. c1. 170160.46)

This invention relates to engine cooling fan arrangements and more particularly to a novel mechanism for reversing the pitch of such a fan.

A general object of the invention is to provide a novel manually operable mechanism for reversing the pitch of the blades of the engine fan whereby the fan is caused to blow the air forwardly through the radiator or to draw the air through the radiator onto or against the engine.

'In industrial power and farm implement applications such as tractors wherein the equipment operates in the fields where dirt, chaff and the like is sucked against the radiator, it is desirable to provide an economical and rugged means for periodically removing such dirt and chaff out of the radiator.

A specific object of the invention is to devise a novel mechanism which is adaptable to current engine arrangements and wherein the instant invention constitutes a replacement package for the standard fan arrangement without major change in the basic construction of the engine unit.

These and other objects of the invention will become more apparent from the specification and the drawings, wherein:

Figure 1 is a fragmentary side elevation of an engine unit incorporating the invention;

Figure 2 is a longitudinal sectional view through the operating mechanism taken substantially on the line 22 of Figure 3;

Figure 3 is a fragmentary front elevational view of the structure shown in Figure 2 with portions removed in order to more clearly illustrate the invention;

Figure 4 is a plan view showing the normal running position of the fan in solid lines and in the blow-back position of the fan in dotted lines;

Figures 5 and 6 illustrate a modification of the invention, Figure 5 being a fragmentary front elevational view partially in longitudinal section.

Describing the invention in detail, the engine 2 is of conventional design and has the front end of its crankshaft 3 keyed to a pulley 4 about which is trained a fan belt 5 which, of course, may be trained about the generator pulley, not shown, and about the fan pulley 6 which in the present instance is formed integral with the inner end of a cylindrical fan carrier or hub 7 which adjacent to its outer extremity is provided with a plurality of radially extending journal members or holders 8 each of which rotatably receives a shaft 9 to the outer extremity of which is secured as by welding or riveting a fan blade 10. The inner end of the shaft 9 is connected to an eccentric or crank 11 which is encased within the housing or tubular portion 7. The outer or rear end of each crank 11 is pivotally connected as at 12 to the outer I projections 15 on the member 16. The inner end of the housing 7 is provided with four internal radially inwardly extending ribs 17 which define spaces or interstices 18 therebetween through which the aforementioned lugs or projections 15 of the motion transmitting member 16 extend. The inner extremities of the ribs 17 are joined to a hub 19 which is interlocked with a pump or impeller shaft 20, as will be readily understood by those skilled in the art. The pump shaft is suitably rotatably supported within the pump housing 21 which provides a generally tubular forwardly extending body portion 22.

The body portion 22 of the pump 21 is surrounded by a return spring 23 which is seated at its forward end as at 25 against suitable bearing surfaces 26 formed on the back sides of the ribs 17 adjacent to their juncture with the casing 7 which is continued into the aforesaid pulley 6, the inner periphery 27 of the pulley complementally receiving the cylindrical member 16 whereby the interior of the housing 7 is, with the cooperation of the cover plate 28 which is seated and bolted against the outer edge 29 of the housing 7, substantially sealed against the entry of dirt.

The rear extremity of the return spring 23 is seated and bears against a shoulder 30 defined by the inwardly offset ring portion 31 formed integral with the member 16 at its rear extremity. The ring member 31 provides an external circular groove 32 which receives a split band 33 therein for relative rotation with respect thereto.

The collar 33 is provided at diametrically opposite sides with trunnion pins 34 and 34' (Fig. 3) which operate within elongated slots 35 and 36 formed in the bifurcated lower end portions of the legs 37 and 38 of a shifting fork generally designated 39, the said legs 38 and 39 being joined as at 40 and being pivotally mounted on a shaft or pin 41 intermediate their ends from a fulcrum structure 43 which is suitably connected as by bolts 44 to an adjacent portion of the engine.

The upper end 45 of the shifting fork 39 is pivotally connected as at 46 to the forward end of an operating rod 47 which is extended and suitably mounted within easy reach of the operators station.

Operation of the device In operation the spring 23 which is normally in compression between the member 16 and the member 7 through the medium of the shoulder 38 and the ribs 17 maintains the fan blades in normal operating position, that is drawing the air through the radiator 50 which is positioned immediately thereahead and blowing the air onto the engine. If the operator should desire to reverse the direction of the movement of the air by the fan he will pull the operating member 47 rearwardly referring to Figure 2, that is to the left, whereupon the shifting fork rotates in a counterclockwise direction and thereby the member 16 is moved forwardly, that is to the right, for obtaining, with the compression of the spring 23, forward movement of the links 13 and rotation of the cranks 11 in a counterclockwise direction as shown in Figure 2 in phantom lines whereupon the fan blades assume the position shown at 50a in Figure 4. It will be readily appreciated that (as shown in Figure 4 in phantom) the fan, which is normally rotated in a clockwise direction, will blow the air forwardly. In order to return the mechanism to normal operating position all that the operator has to do is release the operating rod 47 and the spring 23 will expand thereby moving the member 16 rearwardly and pulling on the operating links 13 rearwardly and rotating the cranks in a clockwise direction, as seen in Figure 2, and thus restoring the fan blades to their original position.

Referring now to Figures 5 and 6, the bearing portion is comparable to the bearing portion 22 of the preceding embodiment and is ensleeved by a pulley 101 which is driven by a belt 102 trained thereabout, the fan belt 102 corresponding to the belt of the preceding embodiment. The pulley 102 is formed integral with the inner end of a tubular or cylindrical carrier member or hub 103 which at its forward end is closed by. an end wall 104 which merges into a central hub 106 which is keyed to the shaft 167 of the water pump, the shaft 107 being journaled in the bearing member 100. The forward extremity of the carrier 103 is connected as by bolts 168 to a spider member which includes a plurality of radially outwardly extending arms 11%) extending from the corners of the polygonal-shaped central portion 111 which is formed by interconnected side members 112.

Each of the members 112 comprises a radially extending bore or opening 113 receiving a shaft 114 journaled therein, the inner end of the shaft having a suitable securing member 115 connected thereto and rotatively abuttable against the interior edge 116 of the related member 112 to prevent outward displacement of the shaft 114.

The outer end of each arm 110 is formed with a generally circumferentially directed lug'118 and in which journals the intermediate portion of the related shaft 114, in an opening 119, and the outer cndof each shaft is connected to a fan blade 120.

Each extension 118 and the related arm and side portion 112 of the spider form a C-shaped pocket 122 through which an intermediate portion of the related shaft 114 extends and this intermediate portion is ensleeved by a crank arm 124 which is connected to the shaft as by pin 125 for rotation therewith, the outer end of the arm beirig pivotally connected on an axis parallel to the associated shaft 114 as by a pin 126 to the outer forward end of an operating link 127 which at itsinward or rear end is pivoted as by a bolt 128 on an axis parallel to the related shaft 114 to a ring member 129. It will be noted that the members 127 are disposed externally of the ring 129 and that the said ring 129 has a central opening 130 which has a complemental fit with theouter periphery 131 of the carrier member 103. The rear portion of the member 129 is recessed to provide an internal groove 134, defined at forward extremity by a rearwardly facing shoulder or seating surface 135 for seating the forward end of a compression type return spring 136 which is ensleeved about the member 103 and at its rear extremity seats against the outer or forward side as at 137 of the forward flange 138 of the pulley 101.

The rear portion of the motion transmitting member 129 is provided with an annular external groove 140 for receiving the split collar such as 33 in the previous embodiment and which in turn is adapted to be associated with the shifting fork arrangement as the assembly 39 adequately shown in a previous embodiment, as will be readily understood by those skilled in the art.

Figures 5 and 6 illustrate the normal position of the fan Whereat it draws air through the radiator and blows it against the related engine. If the operator should desire to reverse the pitch of the fan blades he merely pushes on the operating linkage and this is reflected in rearward movement of the member 129, which is to the left in Figure 6, whereby pulling the links 127 in a similar direction and rotating the respective fan shafts 114 in a counterclockwise direction and positioning each blade as shown in phantom lines at 120a in Figure 6.

Assuming that the direction rotation of the fan in its normal running position is clockwise, as seen in Figure 5, this same rotation with the changed pitch of the blade will effect the reverse flow of the air. Of course, when the operatorreleases the linkage which holds the member 129, the spring 13 6 expands and disposes the parts in the position shown in Figure 6.

It will be readily appreciated that both embodiments illustrate an effective manually operated arrangement for reversing the pitch of the fan and thatboth embodiments are readily adaptable for mounting in the conventional fan arrangement without any basic changes or reorganization of the original engine structure.

What is claimed is:

l. The combination of a shaft, a cylindrical carrier member surrounding said shaft and having a hub structure connected to said shaft; a belt pulley on said member and constrained for rotation with said member; fan blade mounting means on said member adjacent to one end thereof and constrained for rotation with said member; a plurality of fan blade assemblies each comprising a spindle, said assemblies arranged in a radially extending circumferentially spaced array with the spindles mounted in said mounting means for rotation on their individual axes; a motion transmitting cylindrical member disposed in telescoped relationship with said first-mentioned member and in complementary supported peripheral engagement therewith and in concentric placement to said shaft and slidable axially relative to said firstmentioned member; a helical coil spring coaxial with said members; opposed abutments on respective members seated against opposite ends of said spring; said spring being under compression and operative to urge said members in opposite directions, a crank connected to each spindle for rotating the related fan blade assembly; an operating link operatively connecting each crank with said motion transmitting member; and manually operative means connected to said motion transmitting member for moving the same axially against the resistance of said spring and actuating said links for rotating said cranks and thereby said fan blade assemblies for changing the pitch thereof.

2. The combination according to claim 1 and further characterized in that said hub structure includes a plurality of spokes defining axial interstices therebetween; and said motion transmitting member having lug projections extending through said interstices and interlocking said members for rotation together and providing attachment points for said motion transmitting member to the several links.

3. The invention according to claim 1 and further characterized in that said motion transmitting member is disposed outwardly of said carrier, and said spring is sleeved over the carrier and said belt pulley has a flange providing said abutment on said carrier member and said motion transmitting member has a shoulder opposing said pulley and providing an opposed seating surface for the opposite end of the spring.

4. The combination of a shaft, a cylindrical carrier about the shaft and having an inner end with a fan belt driven pulley, and having an outer end with a plurality of radially extending holders disposed in a circumferentially spaced series; a spindle journaled in each holder, a fan blade connected to the outer extremity of the spindle, a crank connected to the inner end of the spindle; a motion transmitting cylindrical member telescoped within said carrier and projecting inwardly of said inner end of said carrier; a skeletal hub structure integral with said carrier therewithin and spindled upon said shaft and including a plurality of radial spoke-like elements defining a plurality of axial opening through said carrier; said motion transmitting member having a plurality of axially directed lugs at its outer end extending through said openings in intercalated relationship with said elements; link means operatively connecting each lug to an adjacent crank for rotating the latter attendant to movement of said motion transmitting member in an axial direction, a return helical spring about said shaft within said motion transmitting member; opposed abutment means on said carrier and said motion transmitting member seating opposite ends of the spring; and operating means connected to said motion transmitting member for shifting it axially.

5. The invention according to claim 4 and further characterized in that said operating means comprises a collar in grooved engagement with said motion transmitting member, a shifting fork assembly operatively connected to said collar, and an operator reach rod connected to said fork for manipulation by an operator.

6. The combination of a shaft, a carrier comprising a tubular member surrounding said shaft, said member having an integral hub structure adjacent to one end spindled on said shaft; a fan belt pulley on said member and constrained for rotation with said member; fan blade mounting means on said member spaced from the hub structure and constrained for rotation with said member; a plurality of fan blade assemblies each comprising a spindle, said assemblies arranged in radially extending circumferentially spaced array with the spindles mounted in said mounting means for rotation on their individual axes; a motion transmitting cylindrical member disposed in telescoped relationship with said first-mentioned member and in complementary supported peripheral engagement therewith and in concentric placement to said shaft and slidable axially relative to said first-mentioned member; opposed abutments on respective members; a helical spring compressed between and seated against said abutments for urging said members in opposite directions; a crank connected to each spindle for rotating the related fan blade assembly; an operating link operatively connecting each crank with said motion transmitting member; and manually operative means connected to said motion transmitting member for moving the same axially against the resistance of said spring and actuating said links for rotating said cranks and thereby said fan blade assemblies for changing the pitch thereof.

References Cited in the file of this patent UNITED STATES PATENTS Re. 14,838 Hoiland Apr. 13, 1920 554,331 Bray Feb. 11, 1896 1,327,381 Furber Jan. 6, 1920 1,391,517 Sohn Sept. 20, 1921 1,514,874 Street Nov. 11, 1924 1,636,286 Christensen July 19, 1927 1,712,883 Groner May 14, 1929 2,423,140 Earley et a1. July 1, 1947 

